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-----------------------------------------------------------------------
- Locking issues case 3:
- After creating a snapshot, other clients updating rows
- using READ COMMITTED transaction isolation level
-----------------------------------------------------------------------
DROP TABLE IF EXISTS t0;
CREATE TABLE t0(id INT AUTO_INCREMENT PRIMARY KEY, value INT);
Inserting 200,000 rows
connect con1,localhost,root,,;
connect con2,localhost,root,,;
connection con1;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
SELECT * FROM t0 WHERE value > 0 FOR UPDATE;
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
UPDATE t0 SET VALUE=VALUE+1 WHERE id=190000;
connection con1;
id value
190000 1
ERROR: 0
connection default;
disconnect con1;
disconnect con2;
DROP TABLE t0;
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